Researchers at Oxford University have developed a compact multiple electromagnet that will allow the development of low-cost small particle accelerator for medical applications such as proton and carbon ion therapy, and Accelerator Driven Subcritical Reactor applications for alternative, sustainable and safer nuclear power generation.
Traditionally, very large scale particle accelerators such as synchrotrons and cyclotrons have been used for investigating the structure of matter, but today Fixed-Field Alternating Gradient (FFAG) accelerators are becoming increasingly important.
With a small footprint, FFAGs are ideal for use in applications such as radiotherapy where lower particle energies are required. FFAGs offer a number of advantages in comparison to conventional accelerators. A key requirement for FFAGs is that the electromagnets themselves have to be short in length to fit into the reduced circumference of the accelerator. For FFAGs the required bore of the magnets is another important consideration – it needs to be large enough to accommodate the beam and allow radial orbit excursions of the particles.
When an electromagnet has a large aperture and a short length the effects of the coil ends become predominant. A disadvantage of conventional magnets is that the coil ends do not contribute to the useful field and can also add unwanted field harmonics leading to beam loss.
The Oxford invention relates to electromagnets for bending and focussing high energy charged particles in particle accelerators such as FFAGs. The proposed special winding configuration for normal or superconducting electromagnets is a variant of helical coils, which in general allows the creation of arbitrary multipole or combined function magnets.
The winding configuration is specifically suitable for generating high magnetic fields in short, large aperture magnets with good field quality where end effects are a concern. Another implementation of the design allows varying individual multipole strengths along the magnet axis, which mitigates alignment problems for a given system, thus reducing costs.
The magnet design should be of interest to companies involved in development of small accelerators for ADSR and medical applications including radiotherapy, biomedical research and radioisotope production.
This work is the subject of two UK patent applications, and Isis would like to talk to companies or investors interested in commercialising this opportunity. Please contact the Isis Project Manager to discuss this further.
For more information, contact Isis Innovation, quoting reference: Project Number 4351 - Smart Electromagnets Empower Small Particle Accelerators.